


Who's Taking Sides

by slipintothewater (secondstar)



Category: Supernatural, Teen Wolf (TV)
Genre: Alternate Universe - Fusion, Canon-Typical Violence, Crossover, Demon!Stiles, Demonic Possession, M/M
Language: English
Status: Completed
Published: 2012-10-30
Updated: 2012-10-30
Packaged: 2017-11-17 09:52:32
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,459
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/550290
Author URL: https://archiveofourown.org/users/secondstar/pseuds/slipintothewater
Summary: <blockquote class="userstuff">
              <p>When Scott tells Allison that Stiles smells of sulfur, she calls the Winchesters in desperation.</p>
            </blockquote>





	Who's Taking Sides

**Author's Note:**

> Written for halloweencow@tumblr's gifset! 
> 
> Originally was supposed to be a commentfic but obviously, got too long. 
> 
> Unbeta'd.

Allison knew she only had one option, she knew that in order to save her friend she had to call them. The Winchester family had been close to The Argent’s, back when John was alive. Allison remembered Sam and Dean coming to stay with them when she was younger, that Mr. Winchester dropped them off for weeks at a time. Now was not the time to reminisce, though. Stiles needed help, and Allison couldn’t think of anyone else to call. 

“Sam? It’s Allison Argent,” Allison said into the receiver as she ran her fingers through her hair. “I need help.”

“Allison?” Sam asked, looking at his brother Dean with raised eyebrows as he held the phone against his ear. “What’s wrong?” He asked, genuine concern etched across his face, dripping from his voice empathetically. 

“It’s one of my best friends, his name is Stiles,” Allison said, taking a deep breath before continuing. “He’s been possessed by a demon. Dad doesn’t do... demons.” 

“Where are you guys living now?” Sam asked, starting to pack his bag while Dean waited to hear what was going down. “Does the demon know you’re onto him?” 

“We’re in Beacon Hills, California,” Allison whispered, biting on her bottom lip. “It doesn’t know, my boyfriend... smelled the sulfur. Stiles smells of sulfur, strongly.” Sam looked to Dean, his eyebrows raised. He covered the phone with his hand. 

“Allison says her boyfriend smelled the demon in this kid,” Sam whispered. Dean pursed his lips, his eyebrows knit together, thinking. 

“How?” He asked, to which Sam shrugged his shoulders. “That... humans can’t smell demon on someone-”

“How did they do that, Allison? Smell the demon-”

“Listen, guys. I just... I really need your help with Stiles, I have no where else to turn to. I am actually reaching out without even really talking about this with my boyfriend and his friends, which is a big deal. If you can’t come, at least email me the latin to read off and I will get him in a devil’s trap myself-”

“No, no. Allison, it’s fine. We’re coming, the latin is complicated and you don’t want to piss off a demon, they may kill your friend.”

“Which would be really, really bad,” Allison whispered. “For a lot of reasons. How soon can you get here?” 

“We’re about to leave now, we’ll be there as soon as we can.”

 

Sam and Dean rolled into Beacon Hills at three thirty in the morning. Both Allison and Chris Argent were awake still, when Sam and Dean knocked on their front door. Allison hugged both of them, since she hadn’t seen them since she was a young girl. 

“It’s good to see you boys,” Chris said as he pat them both on the back as they hugged. “Sorry it is under these circumstances.” 

“And we’re sure that he is a demon?” Dean asked. “I’ve never heard of a human being about to smell the sulfur of a demon-” Chris and Allison exchanged glances, which caught Dean’s attention. “Unless there is something you need to tell us.”

“My boyfriend, he’s a werewolf,” Allison said, pulling the band aid off quickly. Sam’s eyebrows shot up as he looked to Chris, who nodded slowly. 

“This isn’t about the werewolves. This is about Stiles, a human who, according to Scott, hasn’t been acting like himself and smells distinctly of sulfur. Allison tells me that Derek, who is also a werewolf, has noticed... as well.”

“And this human, he runs with these wolves?” Sam asked, confused. Allison nodded his head. 

“We both do. We’re considered pack,” she said slowly. “The werewolves aren’t an issue here, you need to understand that. Derek is worried about Stiles, we all are.”

“You keep mentioning Derek,” Dean said, “like Stiles means something to him, above.. pack, is that what I am hearing?” Dean asked, wanting the truth. Allison went rigid for a second, her gaze falling to her father for a split second. She nodded. 

“Derek and Stiles are well, complicated. We’ve been trying to act normal around him, we don’t know what the demon wants, really.” 

“Well, first thing’s first,” Dean said as he followed Chris and Allison into the study. “We need a place that human Stiles would go, so that we can make a devil’s trap. I assume he doesn’t come here daily.” 

“Derek’s house. He goes there.” 

“The alpha’s den?” Dean asked, scoffing. “You want us to go into an-”

“Yes, that will work fine,” Sam said, shooting his brother a look. “We don’t want to tip the demon off too early that something is wrong.” 

Chris leaned over his desk and sighed. 

“You need to know that we have a truce with this pack of werewolves, we have a code. No one in the pack has spilled human blood, that-”

“We get it, alright?” Dean said as he sat down on a couch. “We aren’t here for the werewolves, we’re here for Stiles.” Dean got out a gun to clean, to keep his hands busy as they talked through things. “So, you have school today, right?” Dean asked Allison. Allison nodded. 

“Can you talk to this alpha, let him know that we’re coming to his place to get ready?” Allison nodded her head. “Your job, and your boyfriend’s, is to make sure Stiles gets to Derek’s. The less people there, the better.”

“Make sure that Lydia doesn’t get mixed up in this,” Chris whispered. “And tell Derek the rest of the pack shouldn’t be there.” Allison nodded. “I don’t even want you there-”

“Dad, this is Scott’s best friend. I will be there.” 

Sam and Dean pulled up to the burnt out house that Allison described to them. Glancing at each other as they got out of Dean’s impala, they walked up the steps leading up to the front door. Before they even reached for the door, it swung open. Derek Hale stood there, his brow furrowed and lips pursed. 

“Allison told you we were coming?” Sam asked, hopeful. Derek’s expression didn’t changed but he nodded, swinging the door open to let them in. 

“Nice place you’ve got here,” Dean murmured. Derek’s gaze darkened. Dean ignored him. 

“Where can we, uh, defile your ceiling?” Sam asked, shaking a can of spray paint. Derek lead them into what used to be a living room. 

“This room has the most intact ceiling, is this good?” Derek asked, his voice terse. 

“It will work,” Dean said, sighing. “So you can smell it too? The sulfur?” Derek’s nostrils flared for a second, but then he nodded. 

“It isn’t Stiles. His scent changed completely, his movements aren’t the same and the pitch in his voice... his quirks aren’t his. It is like someone else is in Stiles’ body.” Sam and Dean exchanged glances once more. 

“We can fix this,” Sam assured Derek. “If we catch him off guard, Stiles should be okay.”

“ _Should be_ being the operative word there. There could be complications.” Derek clenched his jaw at Dean’s words. “Hey, man, I am just being honest with you here.” 

“We, of course, don’t want Stiles to be hurt. We don’t know what the demon has been doing to him, honestly. Every demon is different. Even if Stiles is fine physically....” Sam trailed off. “Who knows what it’s done to him mentally.” Dean nodded at Sam’s words. 

“Stiles is probably living his own personal hell right now, there is no telling.” 

“We just want him back in one piece.” 

Stiles arrived after school with Scott and Allison, like planned. Derek was in the living room, waiting, just like it was discussed. Allison and Scott walked in and made themselves comfortable on the couch, in the middle of the room. Stiles, though, skirted the outside of the room, his eyes narrowed. Allison bit her lip, looking at Stiles worriedly. 

“You know, I’m thirsty. Do you want anything Scott?” Allison asked. Scott nodded, shrugging like he normally did. “Stiles, do you want something?” She asked, her tone the same as when she asked Scott. Stiles smiled.

“Sure,” he said, his eyes falling on Derek’s frame, by the fireplace. Stiles stepped into the room as soon as Allison was out, making his way to the empty spot on the couch by Scott. As soon as he did, Scott was off the couch and into the entryway. Sam and Dean walked into the room. Stiles turned to see them. 

“Winchesters? Here?” He asked. Derek took a step towards Stiles, “Stop right there, Hale. Or you’ll regret it.” Derek stopped where he was, looking to Sam and Dean for suggestions. Sam had a knife, while Dean had a gun. Derek didn’t want them to use either of them. 

“What do you want with Stiles?” Sam asked. The demon looked at Sam momentarily before shoving his hands in his pockets as he looked up at the ceiling, pacing slowly around the room. He shrugged, his attention back on the Winchesters. 

“Why not? I mean, the kid as some interesting views on life, on his place in the pack,” Stiles, the demon, glared pointedly at Derek, then at Scott who was still in the entryway. “I feed off of paranoia, you know, of insecurity. Stiles, he was practically bursting with it-”

“Enough,” Derek growled. “Leave him alone.” Stiles lifted his eyebrows, his eyes fading to black within the blink of an eye. 

“You’ll have to kill me first, which unfortunately....” Stiles trailed off, shrugging as if he didn’t care. 

“Now, Derek!” Dean said, then suddenly Dean, Sam, and Derek managed to hit the demon with holy water, which they put into water bottles strategically strewn across the room. Stiles fell the to ground, clawing at his flesh. Derek’s eyes were wide, his fists clenched as he watched Stiles writhe in pain on the floor. 

“Is he, is this permanent?” Derek asked as Stiles’ screams filled the room. 

“You should probably leave, because this is about to get messy-”

“No,” Derek said through gritted teeth as he watched Sam and Dean pace around him as he flailed about in pain. 

“Fine, but if the demon lets the real Stiles come to the surface, you have to let Dean and I do what we have to do,” Sam said, his voice harsh. Derek nodded once in compliance. 

Sam got out his book, and began reading out the latin incantation to rid Stiles’ body of the demon. In the middle of it, the demon came to, struggling and panting against the words as if pinned in place. 

“You think that you can just expel me and that I won’t just come back later?” He spat, his eyes blackened, teeth snarling. “I’ll jump back in this kid’s body so fast you won’t stop me from killing him.” Derek took a step forward, clearly worried. Dean stopped him. Sam continued chanting as Dean turned towards Derek. 

“You have to make a decision now, expel him for now, temporarily, or permanently.”

“What is the difference? What would you do to him?” Derek asked, his eyes fixed on Stiles, his eyes blackened, a smirk on his face. 

“We have a knife, it kills demons-”

“You’d have to stab Stiles?” Derek asked. Dean nodded. 

“I can pick... I can do it so it won’t kill him,” Dean reassured Derek. Derek nodded. 

“Permanently gone, then.” 

“Sammy, stop,” Dean said, his voice gruff. Sam stopped chanting, his brow furrowed in confusion. Dean grabbed the knife and Sam nodded knowingly. “See this, you demon piece of shit?” 

The demon’s black eyes disappeared and Stiles, the real Stiles’ eyes were wide, his mouth open in a panic. 

“No, please, stop, don’t-”

“Stiles,” Derek said, rushing forward. “It’s Stiles, you can stop now.” 

“No, the demon is still inside him. We need to do this,” Sam said, holding onto Derek’s shoulder. Stiles looked up at Derek, shivering, his teeth raking across his bottom lip. 

“Derek-” Dean slammed the knife into Stiles’ hand, causing him to scream and shake violently as the demon inside him expired. Stiles slumped forward and Derek was there, grabbing him and holding onto him as they sat on the floor. Derek gathered Stiles in his lap as Allison ran into the room with a minimal first aid kit. “Jesus Christ that was fucking awful,” Stiles sniffed as he watched Allison wrap his hand. “How the fuck am I going to explain this to Mrs. McCall and my dad at the ER?” he asked. 

Derek couldn’t help but smile as he looked from Stiles to the Winchesters. 

“Thanks, for saving him,” He mumbled. Sam and Dean nodded. 

“Glad we could do it,” Sam whispered. 

After spending two hours in the ER with a frantic father who couldn’t understand how, exactly, that Stiles managed to stab himself with a knife, and a skeptical Mrs. McCall, Stiles walked out slightly drugged and in a lot of pain. Instead of Derek driving them straight to his place, they ended up at the Argent’s instead. 

“I want to thank you,” Stiles whispered as he looked down at his hands. He and Derek were on the couch in the Argent’s living room, sitting across from Sam and Dean while Chris stood off to the corner. “I shouldn’t have been messing with things I didn’t understand.”

“What?” Sam asked, looking at Dean momentarily before staring back at Stiles. “You mean, you summon a demon?” Stiles shrugged, swallowing down his failure, unable to look at them. 

“I didn’t know, I didn’t realize what I was doing.”

“Obviously,” Dean said, his voice intolerant. “You could have died, you could have killed your friends, your family.” Stiles looked at the floor, dejected, shoulders slumped.

“Why would you do that?” Derek asked. Stiles scoffed. 

“To be stronger. I was stronger, you know? The demon let me... be me, until it sensed danger. I just didn’t want to be the weak human that gets kidnapped and beat up-”

“Stiles,” Derek said, his eyes closing to keep from yelling. “We talked about this,” he said through gritted teeth. “You aren’t weak.” Stiles sighed, exasperated. 

“Well, it doesn’t matter now, does it? No more demon. It’s gone, dead,” Stiles turned back to Sam and Dean. “Thanks, though. Seriously. I didn’t know that it wouldn’t let me go, I was being stupid.”

“I’ll say,” Dean said under his breath as he stood up. “But I am glad you got your shit sorted, kid. But know this: Sammy and I? We’re both human and we don’t take shit from anyone or anything. You are only weak if you think so.”

Stiles looked up at Dean in awe, his eyes wide. “All you need is some training,” he said, looking to Chris Argent, who smiled from where he was leaning against a door frame. “That’s all.”


End file.
